1. Field of the Invention
The present invention relates to a battery control device that controls a battery including a plurality of battery cells. More specifically, it relates to a battery control device capable of executing optimal control for a battery installed in a vehicle equipped with an electric drive device such as an electric car, a hybrid car or an electric train and it also relates to a battery system that includes the battery control device.
2. Description of Related Art
A battery module in the related art is typically constituted by connecting a plurality of battery groups each made up with a plurality of battery cells connected in series, as disclosed in, for instance, Japanese Laid Open Patent Publication No. 2005-318750. A battery control device that controls such a battery module includes a lower-order control device that monitors the states of battery cells, provided for each of the battery groups. These lower-order control devices receive commands issued by a higher-order control device via a signal transmission path in which an insulating circuit such as a photocoupler is disposed so as to ensure that the signal transmission path remains unaffected by the potential difference between the lower-order control devices and the higher-order control device.